Many homes and offices are equipped with fireplaces to provide heat during cold weather. The heat is generated by burning logs or log substitutes within the fire chamber of the fireplace. Radiant heat from the burning material heats the room. Although the radiant heat generated by the burning material supplies heat to the room, the majority of the heat generated by the burning material is discharged through the flue of the fireplace and out through the chimney in the form of heated gases. These gasses are required to be discharged for safety reasons and cannot be vented into the home or office without seriously endangering the occupants thereof. It would, however, be a benefit to have a device for capturing at least a portion of the heat from these dangerous heated gasses and transferring the captured heat into the home or office prior to discharging the dangerous gasses out through the flue of the fireplace. Because many existing fireplaces could benefit from such a device, it would be a further benefit if the device could be easily installed within an existing fireplace. Additionally, it would be a further benefit if the device could detect the presence of a fire within the fireplace and activate an air blower unit for blowing air through a heat exchanger positioned within the fireplace at a location that allows heat from the burning material to be transferred to the air passing through the heat exchanger. It would also be a benefit if the device could detect when a fire within the fireplace had burned out and deactivate the blower.